Treatment of neurodegenerative diseases and cancer of the brain using histone deacetylase inhibitors

ABSTRACT

The present application is directed to a method of treating diseases of the central nervous system (CNS) comprising administering to a individual in need of treatment a therapeutically effective amount of an inhibitor of histone deacetylase. In particular embodiments, the CNS disease is a neurodegenerative disease. In further embodiments, the neurogenerative disease is an inherited neurodegenerative disease, such as those inherited neurodegenerative diseases which are polyglutamine expansion diseases. The individual can be a mammal such as a primate or human.

RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/329,705 filed on Oct. 16, 2001. The entire teachingsof the above-referenced application are incorporated herein byreference.

BACKGROUND OF THE INVENTION

[0002] Compounds which inhibit histone deacetylase (HDACs) have beenshown to cause growth arrest, differentiation and/or apoptosis of manydifferent types of tumor cell in vitro and in vivo. HDACs catalyze theremoval of the acetyl group from the lysine residues in the N-terminaltails of nucleosomal core histones resulting in a more compact chromatinstructure, a configuration that is generally associated with repressionof transcription. These HDAC inhibitors fall into four generalclasses: 1) short-chain fatty acids (e.g., 4-phenylbutyrate and valproicacid); hydroxamic acids (e.g., SAHA, Pyroxamide, trichostatin A (TSA),oxamflatin and CHAPs, such as, CHAP1 and CHAP 31); 3) cyclictetrapeptides (Trapoxin A and Apicidin); 4) benzamides (e.g., MS-275);and other compounds such as Scriptaid. Examples of such compounds can befound in U.S. Pat. No. 5,369,108, issued on Nov. 29, 1994, U.S. Pat. No.5,700,811, issued on Dec. 23, 1997, and U.S. Pat. No. 5,773,474, issuedon Jun. 30, 1998 to Breslow et al., U.S. Pat. No. 5,055,608, issued onOct. 8, 1991, and U.S. Pat. No. 5,175,191, issued on Dec. 29, 1992 toMarks et al., as well as, Yoshida, M., et al., Bioassays 17, 423-430(1995), Saito, A., et al., PNAS USA 96, 4592-4597, (1999), Furamai R. etal., PNAS USA 98 (1), 87-92 (2001), Komatsu, Y., et al., Cancer Res.61(11), 4459-4466 (2001), Su, G. H., et al., Cancer Res. 60, 3137-3142(2000), Lee, B. I. et al., Cancer Res. 61(3), 931-934, Suzuki, T., etal., J. Med. Chem. 42(15), 3001-3003 (1999) and published PCTApplication WO 01/18171 published on Mar. 15, 2001 to Solan-KetteringInstitute for Cancer Research and The Trustees of Columbia Universitythe entire content of all of which are hereby incorporated by reference.

[0003] Preferred hydroxamic acid based HDAC inhibitors aresuberoylanilide hydroxamic acid (SAHA) and pyroxamide. SAHA has beenshown to bind directly in the catalytic pocket of the histonedeacetylase enzyme. SAHA induces cell cycle arrest, differentiationand/or apoptosis of transformed cells in culture and inhibits tumorgrowth in rodents. SAHA is effective at inducing these effects in bothsolid tumors and hematological cancers. It has been shown that SAHA iseffective at inhibiting tumor growth in animals with no toxicity to theanimal. The SAHA-induced inhibition of tumor growth is associated withan accumulation of acetylated histones in the tumor. SAHA is effectiveat inhibiting the development and continued growth of carcinogen-induced(N-methylnitrosourea) mammary tumors in rats. SAHA was administered tothe rats in their diet over the 130 days of the study. Thus, SAHA is anontoxic, orally active antitumor agent whose mechanism of actioninvolves the inhibition of histone deacetylase activity.

SUMMARY OF THE INVENTION

[0004] It has been surprisingly discovered that certain HDAC inhibitors,for example, SAHA and pyroxamide can cross the blood brain barrier atsufficient amounts to significantly inhibit HDAC activity causing theaccumulation of acetylated histones in the brain. This discoverytherefore provides for the use of HDAC inhibitors in the treatment ofdisorders of the central nervous system including cancer of the brainand neurodegenerative diseases.

[0005] The present application is directed to a method of treatingdiseases of the central nervous system (CNS) comprising administering toa individual in need of treatment a therapeutically effective amount ofan inhibitor of histone deacetylase. In particular embodiments, the CNSdisease is a neurodegenerative disease. In further embodiments, theneurogenerative disease is an inherited neurodegenerative disease, suchas those inherited neurodegenerative diseases which are polyglutamineexpansion diseases.

[0006] The individual can be a mammal such as a primate or human.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 is a scan of a Western blot and Coomassie stained gelindicating levels of acetylated histone (αAcH3) at the indicatedtimepoints following treatment with vehicle (DMSO) or three doses ofSAHA (100 mg/kg/hr).

[0008]FIG. 2 is a scan of a Western blot and Coomassie stained gelindicating levels of acetylated histone (αAcH4) at the indicatedtimepoints following treatment with vehicle (DMSO) or three doses ofPyroxamide (100 mg/kg/hr).

DETAILED DESCRIPTION OF THE INVENTION

[0009] The present application is directed to a method of treatingdiseases of the central nervous system (CNS) comprising administering toa individual in need of treatment a therapeutically effective amount ofan inhibitor of histone deacetylase. In particular embodiments, the CNSdisease is a neurodegenerative disease. In further embodiments, theneurogenerative disease is an inherited neurodegenerative disease, suchas those inherited neurodegenerative diseases which are polyglutamineexpansion diseases. In a preferred embodiment, the neurodegenerativedisease is Huntington's disease.

[0010] The individual can be a mammal such as a primate or human.

[0011] Therapeutically effective amount as that term is used hereinrefers to an amount which elicits the desired therapeutic effect. Thetherapeutic effect is dependent upon the disease being treated. As such,the therapeutic effect can be a decrease in the severity of symptomsassociated with the disease and/or inhibition (partial or complete) ofprogression of the disease. The amount needed to elicit the therapeuticresponse can be determined based on the age, health, size and sex of thepatient. Optimal amounts can also be determined based on monitoring ofthe patient's response to treatment.

[0012] Generally, diseases of the central nervous system, are referredto as neurodegenerative, indicating that they are characterized bygradually evolving, relentlessly progressive neuronal death occurringfor reasons that are still largely unknown. The identification of thesediseases depends upon exclusion of such possible causative factors asinfections, metabolic derangements, and intoxications. A considerableproportion of the disorders classed as neurogenerative are genetic, witheither dominant or recessive inheritance. Others, however, occur onlysporadically as isolated instances in a given family. Classification ofthe degenerative diseases cannot be based upon any exact knowledge ofcause or pathogenesis; their subdivision into individual syndromes restson descriptive criteria based largely upon neuropathologic and clinicalaspects. This group of diseases presents as several distinct clinicalsyndromes, the recognition of which can assist the clinician in arrivingat a diagnosis.

[0013] However, research in the past decade has uncovered a newclassification of inherited neurodegenerative diseases, thepolyglutamine (polyQ) expansion diseases. In each, the underlyingmutation is an expansion of a CAG trinucleotide repeat that encodespolyQ in the respective disease protein. All are progressive, ultimatelyfatal disorders that typically begin in adulthood and progress over 10to 30 years. The clinical features and pattern of neuronal degenerationdiffer among the diseases, yet increasing evidence suggests that polyQdiseases share important pathogenic features. In particular, abnormalprotein conformations(s) promoted by polyQ expansion seem to be centralto pathogenesis. This class of PolyQ expansion neurodegenerative diseaseare Huntington's Disease (HD), Dentatorubralpallidoluysian atrophy(DRPLA), spinal and bulbar muscular atrophy (SBMA), and fivespinocerebellar ataxias (SCA1, SCA2, SCA3/MJD(Machado-Joseph Disease),SCA6 and SCA7). These diseases are listed in the general listing ofneurodegenrative disease below. Many of these diseases not yet connectedwith PolyQ expansion are thought to result from abnormal protein foldingand aggregation (e.g., Alzheimer's disease).

[0014] Generally, neurodegenerative diseases can be grouped as follows:

[0015] I. Disorders characterized by progressive dementia in the absenceof other prominent neurologic signs.

[0016] A. Alzheimer's disease

[0017] B. Senile dementia of the Alzheimer type

[0018] C. Pick's disease (lobar atrophy)

[0019] II. Syndromes combining progressive dementia with other prominentneurologic abnormalities

[0020] A. Mainly in adults

[0021] 1. Huntington's disease

[0022] 2. Multiple system atrophy combining dementia with ataxia and/ormanifestations of Parkinson's disease

[0023] 3. Progressive supranuclear aplsy (Steel-Richardson-Olszewski)

[0024] 4. Diffuse Lewy body disease

[0025] 5. Corticodentatonigral degeneration

[0026] B. Mainly in children or young adults

[0027] 1. Hallervorden-Spatz disease

[0028] 2. Progressive familial myoclonic epilepsy

[0029] III. Syndromes of gradually developing abnormalities of postureand movement

[0030] A. Paralysis agitans (Parkinson's disease)

[0031] B. Striatonigral degeneration

[0032] C. Progressive supranuclear palsy

[0033] D. Torsion dystonia (torsion spasm; dystonia musculorumdeformans)

[0034] E. Spasmodic torticollis and other dyskinesis

[0035] F. Familial tremor

[0036] G. Gilles de la Tourette syndrome

[0037] IV. Syndromes of progressive ataxia

[0038] A. Cerebellar degenerations

[0039] 1. Cerebellar cortical degeneration

[0040] 2. Olivopontocerebellar atrophy (OPCA)

[0041] B. Spinocerebellar degeneration (Friedreich's atazia and relateddisorders)

[0042] V. Syndrome of central autonomic nervous system failure(Shy-Drager syndrome)

[0043] VI. Syndromes of muscular weakness and wasting without sensorychanges (motor neuron disease

[0044] A. Amyotrophic lateral sclerosis

[0045] B. Spinal muscular atrophy

[0046] 1. Infantile spinal muscular atrophy (Werdnig-Hoffman)

[0047] 2. Juvenile spinal muscular atrophy (Wohlfart-Kugelberg-Welander)

[0048] 3. Other forms of familial spinal muscular atrophy

[0049] C. Primary lateral sclerosis

[0050] D. Hereditary spastic paraplegia

[0051] VII. Syndromes combining muscular weakness and wasting withsensory changes (progressive neural muscular atrophy; chronic familialpolyneuropathies)

[0052] A. Peroneal muscular atrophy (Charcot-Marie-Tooth)

[0053] B. Hypertrophic interstitial polyneuropathy (Dejerine-Sottas)

[0054] C. Miscellaneous forms of chronic progressive neuropathy

[0055] VIII. Syndromes of progressive visual loss

[0056] A. Pigmentary degeneration of the retina (retinitis pigmentosa)

[0057] B. Hereditary optic atrophy (Leber's disease)

[0058] HDAC inhibitors suitable for use in the invention include, butare not limited to the following specific structures:

[0059] Further, HDAC inhibitors which can be useful can include the fourgeneral classes described above: 1) short-chain fatty acids (e.g.,4-phenylbutyrate and valproic acid); hydroxamic acids (e.g., SAHA,Pyroxamide, trichostatin A (TSA), oxamflatin and CHAPs, such as, CHAP1and CHAP 31); 3) cyclic tetrapeptides (Trapoxin A and Apicidin; 4)benzamides (e.g., MS-275); and other compounds such as Scriptaid.Examples of such compounds can be found in U.S. Pat. No. 5,369,108,issued on Nov. 29, 1994, U.S. Pat. No. 5,700,811, issued on Dec. 23,1997, and U.S. Pat. No. 5,773,474, issued on Jun. 30, 1998 to Breslow etal., U.S. Pat. No. 5,055,608, issued on Oct. 8, 1991, and U.S. Pat. No.5,175,191, issued on Dec. 29, 1992 to Marks et al., as well as, Yoshida,M., et al., Bioassays 17, 423-430 (1995), Saito, A., et al., PNAS USA96, 4592-4597, (1999), Furamai R. et al., PNAS USA 98 (1), 87-92 (2001),Komatsu, Y., et al., Cancer Res. 61(11), 4459-4466 (2001), Su, G. H., etal., Cancer Res. 60, 3137-3142 (2000), Lee, B. I. et al., Cancer Res.61(3), 931-934, Suzuki, T., et al., J. Med. Chem. 42(15), 3001-3003(1999) and published PCT Application WO 01/18171 published on Mar. 15,2001 to Sloan-Kettering Institute for Cancer Research and The Trusteesof Columbia University the entire content of all of which are herebyincorporated by reference.

EXPERIMENTAL METHODS

[0060] Mice (2 mice per condition) were injected by intraperitonealinjection (IP) with either SAHA (100 mg/kg), pyroxamide (200 mg/kg), orvehicle (dimethylsulfoxide). Each mouse was administered threeinjections at the indicated dose at 1 hour intervals. After the final IPinjection tissues (brain, spleen or liver) were isolated at the timesindicated. Histones were isolated from tissues essentially as describedby Yoshida et al., (1990) J. Biol. Chem. 265:17174-17179. Equal amountsof histones (1 μg) were electrophoresed on 15% SDS-polyacrylamide gelsand transferred to Hybond-P filters (Amersham). Filters were blockedwith 3% milk and probed with a rabbit purified polyclonalanti-acetylated histone H4 antibody (αAc-H4) and anti-acetylated histoneH3 antibody (αAc-H3) (Upstate Biotechnology, Inc.). Levels of acetylatedhistone were visualized using a horseradish peroxidase-conjugated goatanti-rabbit antibody (1:5000) and the SuperSignal chemiluminescentsubstrate (Pierce). As a loading control for the histone proteins,parallel gels were run and stained with Coomassie Blue (CB). The resultsare shown in FIGS. 1 and 2.

What is claimed is:
 1. A method of inhibiting histone deacetylase in thebrain of a mammal comprising administering to the mammal a histonedeacetylase inhibiting amount of a histone deacetylase inhibitorcompound.
 2. The method of claim 1, wherein the histone deacetylaseinhibitor compound is selected from:

or a pharmaceutically acceptable salt thereof.
 3. The method of claim 2,wherein the histone deacetylase inhibitor compound is selected from:

or a pharmaceutically acceptable salt thereof.
 4. A method of treating adisease of the central nervous system in an individual in need thereofcomprising administering to the individual a therapeutically effectiveamount of a histone deacetylase inhibitor compound.
 5. The method ofclaim 4, wherein the disease is a polyglutamine expansion disease. 6.The method of claim 5, wherein the polyglutamine expansion disease isHuntington's disease.
 7. The method of claim 4, wherein the individualis a human.
 8. The method of claim 4, wherein the inhibitor of histonedeacetylase is selected from:

or a pharmaceutically acceptable salt thereof.
 9. The method of claim 8,wherein the histone deacetylase inhibitor compound is selected from:

or a pharmaceutically acceptable salt thereof.
 10. A method of treatinga brain cancer in a mammal in need thereof comprising administering tothe mammal a therapeutically effective amount of a histone deacetylaseinhibitor compound.
 11. The method of claim 10, wherein the histonedeacetylase inhibitor is selected from:

or a pharmaceutically acceptable salt thereof.
 12. The method of claim11, wherein the histone deacetylase inhibitor is selected from:

or a pharmaceutically acceptable salt thereof.